> There should be an iterator over the entries in the /proc/pid/auxv
> file with a callback that processes each entry. So that the iterator
> could be used not just for finding the AT_SYSINFO_EHDR entry.
Ok, an iterator interface is fine with me, just marginally less efficient
than the searcher when only one tag is actually used (and more efficient if
many tags are used). (I had not proposed any function that would be useful
solely for AT_SYSINFO_EHDR, though that was one of Jim's early
suggestions.) If others agree this is the right interface for a target_ops
addition, I will write that patch.
Actually, I think this is not as useful an interface as one that fetches
the whole block for you. There is another use for this call besides the
Linux-specific AT_SYSINFO_EHDR check: gcore. We want gcore to produce
NT_AUXV notes in core dumps so that those core dumps can be used to extract
whatever AT_* information we could extract from core dumps written by a kernel.
This is easy to add either way, but is cleaner, simpler, and more efficient
if it just writes the whole block uninterpreted than if it dissects and
reassembles it.